Ablation has been used as a tool for treating a wide variety of medical diseases. Laser ablation can induce both thermal and mechanical damage in soft tissue and the extent of this damage is a function of the ablation laser's wavelength, power, spot size, and pulse duration. The efficacy of ablation treatment is a function of the ability to control the accuracy of the targeted treatment volume with minimal collateral damage. Previous studies of monitoring for ablation control relied on surface imaging or post-ablation analysis using histopathology. Using Optical Coherence Tomography (OCT) as an optical monitoring tool we will develop a combined imaging/laser-ablation device for obtaining real-time, depth resolved information regarding the ablation process in order to accurately control the ablation volume while minimizing collateral damage. Our method relies on the unique ability of light to deliver ablative energy while simultaneously interrogating the microscopic structure of tissue. Although our approach is applicable to a spectrum of diseases, we will specifically focus on the treatment of Barrett's esophagus. [unreadable] [unreadable] [unreadable]